A rotary transfer apparatus for transferring poultry from one conveyor line to a second conveyor line is disclosed in U.S. Pat. No. 4,178,659, granted to Michael E. Simonds on Dec. 18, 1979. In that reference, each poultry carcass is maintained on a shackle of the input conveyor line by the capture of the lower part of one of its legs between a pair of parallel spaced rods of the shackle. The rotary member positioned between the two conveyor lines for transferring the poultry carcasses between those lines has a series of equiangularly-spaced stations extending around its circumference, each station having a pair of extending parallel spaced rods of similar configuration to the pair of spaced rods on the shackles of the conveyor lines. The apparatus utilizes guide bars to push a carcass from the pair of spaced rods on a shackle of the first conveyor line onto a respective pair of the spaced rods on the rotary member. After the rotary member has turned approximately 180.degree., a second guide bar is positioned to push the leg of the carcass from the pair of spaced bars on the rotary member onto the pair of spaced bars of a shackle on the second conveyor line.
One disadvantage of the Simonds construction, which is remedied by the subject invention, is that a carcass hanging by only one leg can freely rotate on the respectively-associated shackles of the conveyor lines and on the rotary member. The carcass must therefore be re-oriented prior to a further operation such as evisceration. Also, the relatively short distance of interaction between each conveyor line and the rotary member in this construction limits its rate of transfer of poultry carcasses.
Although no rotary member is involved, U.S. Pat. No. 4,034,440 granted to M. P. D. van Mil on July 12, 1977 discloses another means for transferring poultry carcasses between conveyor lines. However, the transfer apparatus of this reference would necessarily operate at a slower rate then the previously-described apparatus.
An important feature of the rotary transfer apparatus of the subject invention is a knife mechanism for removing the lower part of the legs (sometimes referred to as "hock") of the carcasses. With respect to that feature, one reference of interest is U.S. Pat. No. 3,643,293 granted to Jack J. Rejsa on Feb. 22, 1972. In that reference, poultry carcasses are transferred from a picking line conveyor to an evisceration line conveyor by an intermediately-positioned transfer conveyor. A hock cutter apparatus is positioned in the region of adjacency between the picking line conveyor and the transfer conveyor. The lower part of the legs of each poultry carcass is cut from the remainder of the carcass prior to the carcass being transferred on the transfer conveyor to the evisceration line conveyor.
U.S. Pat. No. 3,522,622, granted to E. J. Crane on Aug. 4, 1970, discloses a hock cutter apparatus in which the lower part of the leg of each carcass is stretched across a support member prior to that lower leg being separated from the remainder of the carcass by a blade having an initial dull portion and a following sharp portion. The blade has a stationary longitudinal position on the hock cutter apparatus, and the lower part of the legs of the carcass are positioned between the fingers of a drag conveyor. The drag conveyor pulls the hock joints (separating the lower part from the upper part of each leg) against the edge of the blade. The blade is driven with a vibratory motion normal to the joint to facilitate penetration of the blade between the parts of the joint.